#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<assert.h>
char* my_strcat(char* str1, char* str2)
{
	char* ret = str1;
	assert(str1 && str2);
	while (*str1 != '\0')
	{
		str1++;
	}
	while (*str1++ = *str2++)
	{
		;
	}
	return ret;
}
int main()
{
	char arr1[20] = "xxxx";
	char arr2[10] = "abcdefghi";
	printf("%s", my_strcat(arr1, arr2));
	return 0;
}